Bestway Alwayz Aire Single Size air mattress w/Built in Pump Comfortable flocked sleeping surface Sturdy coil beam construction Unique rib design helps to eliminate roll off Internal sensors detect air pressure level, continuously and silently engages pump to maintain constant firmness. Indicator light turns on to indicate when the air mattress has reached designated firmness. Reconnecting to the power source, automates pump and will setup the airbed or indicate to turn on the button according to the internal pressure.